This invention relates to tools for fastening two sheets of material together without welding or riveting and, more particularly, to a tool in which the sheets of material are fastened together in a clinching operation.
Sheets of material are most commonly fastened together by the use of welding or by the use of rivets. However, each of these methods has disadvantages. Specifically, welding entails high power requirements and large capital investments and cannot be used to fasten certain dissimilar materials, and riveting also requires high capital investment and produces a rather bulky joint that is unacceptable in many applications. In an effort to overcome the disadvantages of welding and riveting, clinching tools have been developed in which the sheets of material are deformed in a clinching operation to securely join these sheets together without the use of rivets and without the use of welds. Whereas these clinching tools have proven to be generally satisfactory in terms of producing a satisfactory joint as between the sheets of material, the available clinching tools are relatively expensive in original cost and are relatively difficult to repair so that a malfunction of the tool generally requires replacement of the entire tool. Existing clinching tools are also not readily modified to perform different kinds of clinching operations but rather are typically dedicated to a specific clinching operation involving specific materials and specific sheet thicknesses.